Greetings.
I'm having a strange problem with my 1995 Contour 2.0L I-4.
I'm getting intermittent CEL 172. My code scanner hasn't
arrived yet so all I can do currently is watch the CEL
indicator flash.
Brief History is in order.
2.0L I-4 unmodified 1995 Zetec, 109K miles.
Engine Temp got unusually high, to the end of L ("NORMAL")
Tested thermostat, it was seized closed so I replaced it
with Motorcraft standard (192 F).
Temp ran a little high but stable, at A(in "NORMAL").
Then I replaced O2 sensor but still no improvement,
problem still exists.
Finally put in a 180 F thermostat. I'm much happier with the
temp readings at R (in "NORMAL").
BUT ----------------
CEL still comes on intermittently, then goes off about
60 seconds later. Always seems to be code 172.
CEL mostly appears after driving highway speeds (60-70 MPH).
More wierdness, when CEL is on engine temp climbs a little,
then CEL goes out and temp goes back down.
Seems a little down on power but runs smoothly through
entire RPM range; Launch from dead stop is sluggish.
I think 172 means Lean mixture at O2 sensor.
Are there advantages/drawbacks to the 180 F thermostat
over the OEM 192 F?
HELP HELP HELP HELP. I am getting frustrated.
Is it time to take it to the (big bucks) shop or dealer?
Any Suggestions?
Gary J. --- Atlanta
Reply postings or private messages would be appreciated.
